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Anyone know a good source or answers on how to visual light pollution and weather for a site selection study?

Question asked by sleblanc95 on May 3, 2019

So I've been working on project in GIS to select adequate sites for stargazing using a couple of critera including accessibility, weather patterns(cloud coverage), and light pollution. I've narrowed the scope to my state and easily found shapefiles for both state and federal parks/forests and some raw data to start out with. Just a few things pose a challenge.

  1. I found this data for a star chart with constellations, planets, and comets in ArcGIS that I have brought into and display in Pro, just how should I go about aligning it with any static location and time on earth. I'm given plenty of orbital elements such as time, Right Ascension, declination, etc. just need to be able to adjust it accordingly with the projection. I know it's never exact since the earth rotates and bodies closer to earth move faster relative to distant things galaxies, but if I can cut out a circle of the map, dim the edges(horizon), and say this is what the portion of observable sky looks at this point in time( say midnight in Big Bend national park), it'd be great for a visualization. Feel kinda embarrassed having a degree in aerospace and working now in GIS with this project but don't know how to do this alignment myself.

  2. I can easily find different weather pattern datasets but would anyone know where would be the best place or way to find a dataset that's just average seasonal(or annual) cloud coverage or just cloud-free days? I have this problem because NOAA gives me over 2000 results for cloud frequency and I just need a raster dataset for a particular region of the US and any other attempt in google to use "GIS" and "cloud" in the same sentence gives me results on cloud computing.

  3. Lastly I wanna be able to visualize light pollution like in this site(https://www.lightpollutionmap.info/#zoom=4&lat=5759860&lon=1619364&layers=B0FFFFFTFFFF ) and know where to pull it from VIIRS data source( https://ngdc.noaa.gov/eog/viirs/download_dnb_composites.html ) but has anyone had any luck in getting it to show in a gradient, its also a pretty big file over 3Gb so just would wanna know what to do with all that data to cut it down to an area for what my study is focused on.

Otherwise sorry for the trouble in asking

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